Gestational diabetes mellitus (GDM) is elevated blood glucose level (or hyperglycermia) with onset or first detection during pregnancy and represents more than 90% of all pregnancies complicated by diabetes. GDM complicates approximately 4% of all pregnancies in the U.S., affecting about 135,000 cases annually. GDM is associated with significantly increased risks of maternal and infant morbidity, including macrosomia (birth weight > 4000 g), hypertensive disorders in pregnancy (e.g., preeclampsia), cesarean section, preterm birth, shoulder dystocia and birth injury. Women with GDM are at a significantly higher risk of developing type 2 diabetes in their later life. Periodontal disease is the most common chronic disorder of infectious origin in humans and could affect about 20-50% of pregnant women. Periodontal disease results in bacteremia, inflammation, and a strong immune response, representing significant risk factors for the development of certain systemic diseases such as cardiovascular diseases, type 1 or 2 diabetes and adverse pregnancy outcomes. Because there are few previous studies that have examined the possible relationship between periodontal disease and GDM, we propose to conduct this case-control study to examine if periodontal disease is more prevalent in women with GDM than women without GDM. We will recruit 72 patients with GDM and 72 women without GDM during their antenatal care visits. After recruitment, an oral examination will be performed on all cases and controls by a qualified dentist. Periodontal status will be evaluated, and periodontal diseases will be defined by clinical parameters. The proportion of periodontal disease will be compared between women with and without GDM. The long-term goal of this research program is to develop intervention strategies that are based on the risk factors identified in the proposed study. Our study will contribute to an understanding of periodontal disease as a possible risk factor to GDM. Periodontal disease is preventable and curable. If periodontal disease is confirmed as a risk factor for GDM by our study, this will open the doors to intervention studies to prevent GDM. Improving oral health and treating periodontal disease before and during pregnancy may reduce maternal and perinatal morbidity associated with GDM and prevent type 2 diabetes after pregnancy. [unreadable] [unreadable] [unreadable]